Apparatus for controlling oil burners



Apwifi 5W, IQSSO KELLEY I 1,997,797-

APPARATUS FOR CONTROLLING OIL BURNERS I Filed Jan. 5, 1934 Patented Apr. 16, 1935 UNITED sTATEs PATENT OFFICE APPARATUS FOR CONTROLLING OIL BURNERS r James J. Kelley, Medford, Mass. Application January 3, 1934, Serial No. 705,072 2 Claims; (01. 158-424) This invention relates to apparatus for controlling burners,- and more particularly, though not exclusively, to safety provisions for-oil or other liquid fuel burners used in connection with house 5 or other he'aters. 7

One of the common hazards in the use of an oil burner arises from the possibility of smoke damage to the building and its contents in which the burner is located. The possibility of such damage often arises, for example, when the burner, on being automatically started by its thermostatic control, fails to properly function and, creating a back pressure; forces'the heater door open, with the delivery of a stream of smoke into the room in which the burner is' placed. Under certain conditions, in such a case, the delivery of a stream of sooty smoke may be continued, and without any attendant fire hazard, so long as the burner motor continues to run, the smoke permeating adjoining and overhead rooms of the building in which the heater is located, with great resulting damage to property. This is not an infrequent mishap and represents an ever present hazard. The discharge of smoke under such circumstances may or may not be, and often is not, attended by the'discharge of flames from the heater.

One object, among others, of the present in vention is to provide a simple but certain safeguard against smoke damage; provision being made whereby the burner is automatically cut out of operation on the discharge of smoke from the heater if it be continued for more than'a relatively short interval. Another object of the a invention is to provide fire prevention means for stopping the operation of the burner. in case of threatened conflagration due to the external emission of flames from the heater with or without an accompanying smoke stream. 40 The invention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawing:

Fig. 1 shows in outline a heater equipped with an oil burner having associated with it a safety device responsive to the continued discharge of smoke therefrom or to flame emission, and adapted to stop the burner;

Fig. 2 is an enlarged detail in partial section of one form of the safety device;

Fig. 3 is a detail side elevation and partly in section showing the device of Fig. 2; and

. vice generally indicated by Hi.

Fig. 4 is a diagram of circuit connections.

Referring to the drawing and to the embodi ment therein shown for illustrative purposes, in Fig. 1 is illustrated the heater II which may be ofthe steam, hot water or any other desired type.

Theheater is provided with an oil burner l3.

driven by an electric motor I5, this equipment being intended merely as representative of a power driven oil burner of any usual or desired type.

In case the operation of the burner is faulty I This is adapted to thereof.

The discharge of smoke through the throats of such passages or gaps results in the.

deposit of sooty particles on the adjoining faces of the plates of opposite polarity and the closure of the circuit, this in turn effecting the stoppage of the burner, as will be more fully explained.

Referring to Figs. 2 and 3, thesmoke intercepter and responsive device comprises a hood 2 I, which may be of tin or sheet metal with a substantial outward flare at its bottom and contracted at the top to leave a relatively narrow open throat 23. The latter is surmounted by an upright chimneylike extension 25 forming anopen flue for the top of the hood, sothat, due to the radiated heat from the heater, the hood, throat and flue-like extension form a conduit through which there is normally maintained an upward current of air passing into the open flared bottom of the hood, through the open throat and out of the surmounting flue.

Mounted in the conduit, and herein in the fluelike extension, is the smoke responsive control device.

This comprises a spindle 21 of conducoutline and spaced one from another.

Between the plates 3| and alternating therewith, there is supported in fixed position between the frame pieces 29 a second series of spaced, semi-cylindrical metallic plates 33, the latter being held in position by the pins or rods 35 extending from one member 29 to the other and insulated from the flue 25. Each of the plates 3| is spaced from the spindle 2i and from the plates 33, which latter, however, are arranged closely adjacent on opposite sides of the plates 3|, so that when the spindle 2! is adjusted to bring the two sets of plates into coincidence (as shown in Fig. 2) there is left a series of very narrow slot-like passages or gaps presented to the upward ascending current of air and to any smoke carried thereby.

The plates 3| are all electrically connected through the spindle 21 to a conductor 31 and comprise a system of contacts insulated from the conduit walls, while the plates 33 are similarly connected to a conductor 39 through one of the pins 35 and comprise a spaced system of contacts also insulated from the conduit walls. Accordingly, the circuit, including the conductors 87 and 39 and which is normally open at the slot-like gaps, becomes very quickly closed thereat by the deposit of soot on the adjoining plates 3| and 33 which follows the emission of a smoke stream from the heater if such emission is continued for but a very brief interval. The hood 2| serves to gather and concentrate the smoke stream and to intensify its short-oircuiting action.

The spindle 2'! is provided with a handle or button 4| by means of which the plates 3| may be moved out of coincidence with the plates 33 (as indicated in Fig. 3), so that the narrow spaces or gaps between adjoining plates may be reached for the purposes of cleaning when and as required.

The circuiting arrangement through which the safety device acts to stop the operation of the corner when the plates 3| and 33 become shortcircuited is indicated in Fig. 4. Current is normally supplied to the motor |5 from one supply main through the conductor 43, switch 45, contact 41 and conductor 49 connected to one terminal of the motor, and thence from the remaining terminal of the motor through the conductors 5| and 53 back to the other supply main.

The conductors 31 and 39 with the responsive device l9 are connected in a shunt circuit about the conductors 43 and 5|, such shunt circuit including the relay magnet 55. When and if this shunt circuit is closed at H), the magnet 55 becomes energized, attracts one end of the switch lever 45, withdrawing its opposite end from the contact 41, opening the motor circuit, and immediately stopping further operation of the burner. If desired, the magnet-actuated movement of the switch 45 may bring it into engagement with a contact 51, simultaneously operating a signal device, such as the audible signal 59, which latter is included in the circuit 6| connected to the conductor 53.

Associated with the cut-out circuit of the motor, there also provided fire prevention means for stopping the motor in the case of undue emission of flames from the heater. In the illustrated embodiment of the invention this comprises a fuse member 63 (Fig. 2) having a low melting point and located in such a position as to be quickly responsive to flame emission from the heater. In Fig. 2 this is shown as secured to and extending outwardly from the lower edge of the hood 2|. The fuse member 63 holds and supports a generally upright rigid rod 65, the opposite end of which acts as a prop or support for a weight 61. In the event that the fuse 63 melts, the rod 65 drops, releasing the weight 61 and causing the lever 69 to drop. Movement of the lever 69 throws a contact member 1|, connected to but insulated from the lever, against the stationary contact 13. The contact member H is connected to the conductor 39 and the stationary contact 13 to the conductor 31, so that such melting of the fuse closes the shunt circuit, including the conductors 31 and 39 and the relay magnet 55, thereby cutting out the burner motor. The lever 69 is pivoted on an insulating block 15 which also supports the contact 13, the block 19 being secured to the flue-like extension 25.

While for simplicity I have shown the magnetically actuated switch 45 as a simple lever switch, it may, and preferably would, in practice be of a toggle, mercury tube, or such other construction as would cause it, when thrown to motor-circuit opening position, to retain that position until rcset by hand, irrespective of any subsequent reopening of the shunt circuit at the safety device. While I have herein shown and described for the purposes of illustration one specific embodiment of the invention and one particular application thereof, it is to be understood that it may be applied to other use than that herein shown and that extensive deviations may be made in the details,-form and relative arrangement of parts, all without departing from the spirit of the invention.

I claim:--

1. The combination with a heater having flue connections, said heater being provided with an opening and a door therefor, of a liquid fuel burner for said heater, a smoke responsive device, a hood located adjacent and extraneous to said heater and above said opening in position to intercept and direct an ascending stream of smoke emitted into the open air from said heater against said device, and control means rendered operative in response to smoke contacting said responsive device to stop said burner.

2. The combination with a heater having flue connections, of a liquid fuel burner therefor, means for stopping the burner, including means extraneous to said heater and said flue connec tions in the immediate vicinity of said heater and positioned to be responsive to the leakage of smoke into the open air surrounding said heater to actuate said burner stopping means.

JAMES J. KELLEY. 

